1. Field of the Invention
The present invention relates to a washing machine, and more particularly, to a washing machine capable of separating and collecting hydrophobic substances contained in washing water.
2.Prior Art
A general washing machine for washing and dehydrating laundry has, as shown in FIG. 1, a casing 100 for forming an appearance thereof, an outer tub 110 supported by a plurality of suspensions 120 in the casing 100, a washing tub 130 installed in the outer tub 110 in order to accommodate laundry, a pulsator 140 installed at the bottom of the washing tub 130, a driving motor 150 installed under the outer tub 110, and a gear assembly 160 for transmitting the power of the driving motor 150 to the pulsator 140 and the washing tub 130 selectively.
Ducts 200 are formed in the inner wall of the washing tub 130. The ducts 200 form vertical water passages in the inner wall of the washing tub 130. A discharge opening is formed at the upper end of the duct 200, and an inflow opening is formed at the lower end of the duct 200. The washing water in the washing tub 130 flows into the duct 200 through the inflow opening and is discharged from the duct 200 through the discharge opening. A filter 103 for filtering dirt in the washing water is attached to the discharge opening.
A plurality of holes 131 are formed at the side wall of the washing tub 130. The outer tub 110 and the washing tub 130 communicate with each other through the holes 131. Therefore, the water supplied into the washing tub 130 is also supplied into the outer tub 110.
On the upper side of the outer tub 110, a supply pipe 171 for supplying water needed in washing operation into the outer tub 110 and washing tub 130, and a detergent supplier 170 for dissolving detergent with the supplied water are installed.
Under the outer tub 110 is installed a draining device 180 for draining the water in the outer tub 110 during the draining operation and dehydrating operation of the washing machine.
The operation of such a conventional washing machine is as follows.
When a user puts laundry in the washing tub 130 and operates the washing machine, the washing tub 130 is supplied with water through the supply pipe 171. The detergent in the detergent supplier 170 is dissolved by the supplied water, and then the water containing detergent is supplied into the washing tub 130.
During the washing operation, the power of the driving motor 150 is transmitted to the pulsator 140 through the gear assembly 160. Then, the pulsator 140 is rotated so as to generate vortex water flow in the washing tub 130. The laundry accommodated in the washing tub 130 is washed by the vortex water flow generated by the pulsator 140.
When the pulsator 140 rotates, the washing water flows into the ducts 200 by centrifugal force. The washing water flowing into the duct 200 is moved upward, and is discharged through the discharge opening. The dirt contained in the washing water is filtered by the filter 103, and the filtered washing water is re-supplied to the washing tub 130.
As described, laundry is washed by the vortex water flow generated by the pulsator 140 and by the circulating water flow generated by the ducts 200.
During the dehydrating operation, the power of the driving motor 150 is transmitted to the washing tub 130 and the pulsator 140 simultaneously through the gear assembly 160, whereby the washing tub 130 and the pulsator 140 are rotated together at a high rotational speed. Dehydration is performed by the centrifugal force generated in such a situation. During the dehydrating operation, the water in the washing tub 130 is drained outside through the holes 131 and the draining device 180. After the dehydrating operation, a rinsing operation is performed.
However, such a conventional washing machine has the following problems.
The detergent used in washing operation has hydrophilic groups which are polar atomic radicals having great affinity for water, and hydrophobic groups which are nonpolar atomic radicals having little affinity for water and great affinity for oil. The hydrophobic groups contained in the detergent are not dissolved in the washing water completely, so the undissolved detergent is drained together with the washing water during the draining operation, which may cause contamination of water. Furthermore, oil detached from the laundry by the detergent is drained together with the washing water, which also causes the water contamination.
Moreover, in order to get rid of the undissolved detergent in the washing water, the laundry must be rinsed many times, so a great amount of water and time is consumed during the operation of a washing machine.